The present invention relates generally to vehicle parking systems for parking one vehicle on top of the parking place of another vehicle.
Vehicle parking systems for parking one vehicle on top of the parking place of another vehicle are well known. Particularly relevant examples of such systems include the following U.S. Pat. No. 3,941,257 to Matsuura which describes multi-stage parking apparatus with vertically movable pallets which move on a fixed guide track; U.S. Pat. No. 5,158,413 to Wu which describes a car parking frame with upper and lower floors movable by a chain drive assembly; U.S. Pat. No. 5,593,266 to Wurzinger which describes a mechanical lifting mechanism on an arcuate track; and U.S. Pat. No. 5,839,871 to Namgung which describes a double-pallet parking garage in which the pallets are raised and lowered by means of turning links.
A disadvantage of prior art systems, including the above referenced art, is that the framework of the lift apparatus must be safely anchored so that the framework does not move or buckle during operation. This generally requires poured cement moorings or foundations. In addition, relatively powerful motors or hydraulic lift devices are generally required to lift the vehicle, thereby increasing the cost of building and operating the system.
The present invention seeks to provide an improved two-level parking system for parking one vehicle on top of another. Unlike the prior art, the system has a simple and inexpensive construction, yet safely supports a vehicle without any need for anchoring the system to a foundation. The system is characterized by a multiple-lever-arm design that permits lifting the vehicle with a relatively small motor instead of the robust, relatively powerful and expensive motors of the prior art.
The vehicle is lifted along an arcuate track, preferably by means of a chain drive. A pair of lever arms constantly contact the ground and support the vehicle during the initial lifting of the vehicle, and a normal from the center of gravity of the vehicle to the ground does not pass far from ground-contacting surfaces of the lever arms. Up until the point when the vehicle has been lifted onto a support frame, the majority of the vehicle weight is constantly supported by the lever arms, while the frame itself does not have to support much weight. Since the forces and overturning moments acting on the frame are relatively small and insignificant, the frame does not have to be anchored to the floor. The system is also distinguished by quiet, smooth and efficient operation.
There is thus provided in accordance with a preferred embodiment of the present invention a parking system including a plurality of lever arms serially and pivotally connected to each other from a nearest lever arm to a furthest lever arm, each lever arm being movable from a first orientation to a second orientation, wherein an angle of each lever arm relative to a ground surface is greater in the second orientation than in the first orientation, the nearest lever arm being connectable to a support structure for supporting thereupon a vehicle to be parked, and drive apparatus operatively connected to the lever arms and operative to sequentially lift each of the lever arms, starting with the furthest lever arm and ending with the nearest lever arm, from its first orientation to its second orientation.
In accordance with a preferred embodiment of the present invention one or more of the lever arms constantly contacts the ground surface before the drive apparatus lifts the next furthest lever arm from the first orientation to the second orientation.
Further in accordance with a preferred embodiment of the present invention the furthest ground-contacting lever arm of those lever arms which contact the ground surface is pivotably connected at a reference pivot to the nearest lever arm of those lever arms which have been lifted above the ground surface to the second orientation.
Still further in accordance with a preferred embodiment of the present invention there is also provided a support frame and a support structure for supporting thereupon a vehicle, the support structure being pivotally attached at a far end thereof to the nearest lever arm and at a near end thereof to the support frame, wherein the drive apparatus is connected to the near end of the support structure and is operative to move the near end of the support structure along the support frame.
Additionally in accordance with a preferred embodiment of the present invention a vehicle is supported on the support structure, and the drive apparatus lifts the lever arms such that the center of gravity of the vehicle is constantly positioned with respect to the reference pivot such that the total moment produced by the weight of the vehicle and the weight of the support structure on the far side of the reference pivot is not greater than the total moment produced by the weight of the support frame and the support structure acting on the near side of the reference pivot.
In accordance with a preferred embodiment of the present invention the drive apparatus includes a motor which drives a chain drive connected to the near end of the support structure.
Further in accordance with a preferred embodiment of the present invention the support frame includes generally arcuate support rails.
Still further in accordance with a preferred embodiment of the present invention the support frame includes support rails having a generally inverted U-shape with an elongate linear upper portion.
Additionally in accordance with a preferred embodiment of the present invention the chain drive is slidably supported on the support frame.
In accordance with a preferred embodiment of the present invention the support frame includes an anti-friction material underlying the chain drive.
Further in accordance with a preferred embodiment of the present invention the chain drive includes a bridging link pivotally connected to at least one of the lever arms.
Still further in accordance with a preferred embodiment of the present invention safety apparatus is provided which is responsive to slackening of the chain drive, and which locks the bridging link against the support frame.
Additionally in accordance with a preferred embodiment of the present invention the safety apparatus includes a normally retracted, spring-loaded stop member, and a series of protrusions provided on the support frame, so that upon a slackening of the chain drive, free fall of the support frame is prevented by the stop member becoming engaged by a nearby protrusion.
In accordance with a preferred embodiment of the present invention a turntable platform is rotatably mounted on the lever arms.
Further in accordance with a preferred embodiment of the present invention an actuator, operable by rotation of the turntable platform over the lever arms, actuates flaps provided at a vehicle access position on the turntable platform.
Still further in accordance with a preferred embodiment of the present invention a chain blocking member is provided for limiting travel of the chain drive.
Additionally in accordance with a preferred embodiment of the present invention a locking mechanism is provided for locking wheels of a vehicle parked on the ground surface.
In accordance with a preferred embodiment of the present invention the locking mechanism includes at least one platform arranged to move downwards when bearing a wheel of a vehicle thereupon, a pivotable wheel barrier pivoted at a lower end thereof about a pivot, a stop bar pivotally attached to the wheel barrier, adapted to abut against a stationary chock, the stop bar being supported by a pin connected to the at least one platform, wherein when the at least one platform is moved downwards, the stop bar pivots and abuts against the chock.
Further in accordance with a preferred embodiment of the present invention the locking mechanism also includes a linkage arm pivotally connected to the wheel barrier at one end thereof and to a biasing device at an opposite end thereof, a locking bar arranged to move against the linkage arm and to be received in a recess formed in the linkage arm, and a lock mounted at one end of the locking bar which selectively permits movement of the locking bar.
Additionally in accordance with a preferred embodiment of the present invention the locking mechanism also includes a sensor mounted in propinquity to the lever arms which senses and verifies an absence of a person within a predefined zone with respect to the lever arms.